Deciduous
Generally, the term "deciduous" means "the dropping of a part that is no longer needed or useful" and the "falling away after its purpose is finished".
In botany and horticulture, deciduous plants, including trees, shrubs and herbaceous perennials, are those that lose all of their leaves for part of the year.
This strategy is not without risks, as the flowers can be damaged by frost or, in dry season regions, result in water stress on the plant.
[citation needed] Spring leafout and fall leaf drop are triggered by a combination of daylight and air temperatures.
When autumn arrives and the days are shorter or when plants are drought-stressed,[12] the chlorophyll steadily breaks down, allowing other pigments present in the leaf to become apparent and resulting in non-green colored foliage.
The brightest leaf colors are produced when days grow short and nights are cool, but remain above freezing.
Parts of the world that have showy displays of bright autumn colors are limited to locations where days become short and nights are cool.
It is also a factor that the continental United States and southern Canada are at a lower latitude than northern Europe, so the sun during the fall months is higher and stronger.
A number of deciduous plants remove nitrogen and carbon from the foliage before they are shed and store them in the form of proteins in the vacuoles of parenchyma cells in the roots and the inner bark.
Since deciduous plants lose their leaves to conserve water or to better survive winter weather conditions, they must regrow new foliage during the next suitable growing season; this uses resources which evergreens do not need to expend.
[18] This then allows deciduous plants to have xylem vessels with larger diameters and therefore a greater rate of transpiration (and hence CO2 uptake as this occurs when stomata are open) during the summer growth period.
Trees include maple, many oaks and nothofagus, elm, beech, aspen, and birch, among others, as well as a number of coniferous genera, such as larch and Metasequoia.
Most temperate woody vines are also deciduous, including grapes, poison ivy, Virginia creeper, wisteria, etc.
Temperate deciduous forest biomes are plant communities distributed in North and South America, Asia, Southern slopes of the Himalayas, Europe and for cultivation purposes in Oceania.
